The public is being asked to report any hen harrier sightings this year by the ‘Heads Up for Harriers’ project group. Run by the Partnership for Action Against Wildlife Crime (PAW Scotland), this is one part of the effort to help rare hen harriers.
Hen harriers frequent many Scottish moors, where their acrobatic aerial courtship displays are a tell-tale sign of breeding activity. But their distribution and numbers are still restricted in some areas.
A number of causes, including illegal persecution, land use changes and predation, have resulted in a reduction in hen harrier numbers, to the point that the hen harrier is now one of Britain’s rarest birds of prey. In reality, however, many factors are likely to come into play – and the project wants to determine these.
Building upon the successes of 2015, when 10 young hen harriers fledged from 5 participating estates, the Heads Up for Harriers group is extending the project across Scotland. Nest cameras are being used to monitor breeding success at these nests and to help determine some possible causes for any breeding failure.
Locating hen harrier nest sites largely relies on the great work of members of the Scottish Raptor Study Group and sightings submitted by the public. This year is special, however, as there is a national survey of hen harriers, so the project is hoping for a bumper crop of sightings.
Project Officer Wendy Mattingley is responsible for co-ordinating sightings, which in turn help direct fieldwork: She said: “While we do know of historical nesting sites, there is no guarantee that birds will return to the exact location each year. So it’s vital to the success of the project and our understanding of the threats facing these wonderful birds that we receive sightings.”
Male hen harriers are distinctive, with a pale, ash-grey colour, black wing tips and a wingspan of just less than a metre.
Female hen harriers are slightly larger, with an owl-like ‘face’ and mottled brown plumage, which helps to camouflage them when they nest on the ground. They have a very obvious white patch at the base of the tail on the upper side. They could be confused with buzzards but hen harriers are much more agile in flight, with narrower wings which are held inclined upwards in a ‘V’ shape.
The project is working closely with other organisations involved in surveying raptors to share relevant information.
Professor Des Thompson (Scottish Natural Heritage), Chair of the Heads Up for Harriers Group explained: “The information gained from the Heads Up for Harriers Project will feed into the national survey being carried out this year. At the last survey, six years ago, Scotland had around 500 pairs of hen harriers. Based on the amount of suitable habitat and prey species available, we know that the natural carrying capacity is much higher than this. With luck, the survey will reveal an increase in numbers.
“We’re very grateful to the many members of the public submitting records, and the estates which have agreed to participate in the Heads Up for Harriers Project in 2016. This important work could not be carried out without their full cooperation.”
Tim Baynes, Moorland Group Director for Scottish Land & Estates added: “The Heads Up for Harriers Project brings together land managers and harrier experts to work towards the common aim of conserving this special bird. It is by working together that we can understand the reasons for failure and – where identified - promote the recovery of hen harriers in Scotland.
“So far this year, 11 estates have agreed to participate in the project. This is twice as many as last year and includes estates in Angus, Aberdeenshire, Moray, Highland and Dumfries and Galloway, giving good coverage of Scotland. The estates involved include both walked-up and driven grouse moor, and unmanaged moorland, which helps give us a better representation of land use where harriers nest.”